Please explain sense of "keep history" and "keep trends"

[just2blue4u]

Please explain to me the sense of "keep history" and "keep trends" Parameters in "Create Item" Dialog.

I thought "keep history" was to define how long the Values of the Item are stored. But why can i see a graph showing
values from about 1/2 jear ago until now, when the
"keep history" parameter is set to "7 days" ???

And what's this "Trends"-Thing?


What exactly do this 2 parameters describe?
The documentation doesn't really say much about it. Or is it that obvious and i just don't get it?


Pleas help me!

[Alexei]

History - number of days ZABBIX keeps detailed (exact value) history for the item
Trends - number of days ZABBIX keeps trends (30 min avg,min,max,count) for the item

Note that Trends are used for graphs with periods exceeding 24h.

[just2blue4u]

Thank you for making this clear. Now even I understood!

But now please have a look at these values:

Showing history of 3600 seconds(1 h)
[[color=red]from: 2006.Sep.25 14:31:33[/color]] [till: 2006.Sep.25 15:31:33]

2006.Sep.25 15:29:00	730
2006.Sep.25 15:28:00	776
2006.Sep.25 15:27:00	746
2006.Sep.25 15:26:00	680
2006.Sep.25 15:25:00	779
2006.Sep.25 15:24:00	705
2006.Sep.25 15:23:00	701
2006.Sep.25 15:22:00	649
2006.Sep.25 15:21:00	721
2006.Sep.25 15:20:01	773

How does Zabbix know these exact values, if the item has
"update interval" = 60 s,
"keep history" = 7 days and
"keep trends" = 356 days?

[Alexei]

Note that both ZABBIX 1.1 and 1.1.1 had serious housekeeper issues. This probably explains why you have the old data in your database.

[just2blue4u]

Ok, Thank you again.

As i'm installing V1.1.3 on a brand new system, i think this issue should no more appear on my new Server.

Thx 4 helping me that quickly!